112 Observations on the Natural History of the Proteus , fyc. 
mg from it ; c, its bulb ; dd, the two primary trunks arising 
from the bulb, and again subdividing ; e , the first branch 
of the primary trunk, or artery corresponding to the com- 
mon carotid, and which subdivides into two, one branch (f) 
being continued to the first or exterior gill, and the other 
{ g ) proceeding to the muscles of the os hyoides ; A, the 
vein which carries back the florid blood from the gill. 
The second branch of the primary trunk (d) soon also 
subdivides, sending off the branch (?) to the third gill, 
and another ( l ) to the middle gill. To these two 
branchial arteries, the two veins (mm) which carry 
back florid blood, correspond. The principal trunk of 
this second branch, after receiving this florid blood, 
sends off the artery (w), which, descending along the 
air-tube, supplies the air-bladder and generative organs 
in each sex ; it then curves upward, and from its cur- 
vature gives off the vertebral artery (o), which, after 
sending some twigs to the occiput, enters the vertebral 
canal, and descends along it : it also gives off' another 
branch (p) to the temporal bone, and then making 
another curvature downwards, it becomes a branch (q) 
of the aorta, which, by uniting with its fellow of the 
opposite side, it contributes to form. The aorta (?) 
gives off* the branchial arteries (<?<$), the mammary (u) 
and the vessel t going to the stomach ; the letter oc de- 
notes a portion of the vena cava cut off*. 
Plate VII. Fig. 4>. A leaflet of the gill highly magnified, ex- 
hibiting the branchial artery (a), conveying dark blood to 
the gill, and the branchial vein (b), returning florid blood 
to the aorta. 
AiiT. XVII. — Account of the New Galvano-Magnetic Conden- 
ser invented by M. Poggendorff of Berlin. 
r p 
A HE beautiful experiments of M. Ampere on the action 
of spiral conductors, which we have described in our last 
Number, have thrown much light on the new science of electro- 
